Area Code 203 Reverse Phone Lookup

The 203 area code is a telephone area code serving the southwestern part of Connecticut, largely coextensive with the Connecticut portion of the New York metropolitan area. To start a free reverse phone lookup, simply enter the full 10-digit number (including the 203 area code) below and access available caller information such as name, address, and more.

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ConnecticutConnecticut Reverse Lookup ➜

Area Code 203 Location: Connecticut

The 203 area code covers the southwestern portion of Connecticut, including most of Fairfield County, all of New Haven County, and a small portion of Litchfield County.

Counties Served by Area Code 203:

Major Cities in the 203 Service Area:

Other Cities and Towns:

  • Ansonia
  • Beacon Falls
  • Bethany
  • Bethel
  • Bethlehem
  • Branford
  • Brookfield
  • Cheshire
  • Darien
  • Derby
  • East Haven
  • Easton
  • Fairfield
  • Greenwich
  • Guilford
  • Hamden
  • Madison
  • Middlebury
  • Milford
  • Monroe
  • Naugatuck
  • New Canaan
  • New Fairfield
  • Newtown
  • North Branford
  • North Haven
  • Orange
  • Oxford
  • Prospect
  • Redding
  • Ridgefield
  • Roxbury (small part)
  • Seymour
  • Shelton
  • Southbury
  • Stratford
  • Trumbull
  • Wallingford
  • West Haven
  • Weston
  • Westport
  • Wilton
  • Wolcott
  • Woodbridge
  • Woodbury

Overlay System

Area code 203 is overlaid by area code 475. Area code 203 was established in 1947. Area code 475 was added on December 12, 2009. All callers in Connecticut must dial all calls with ten digits.

Area Code 203 Location Map

Area Code 203 Location on Connecticut Map

Area code 203 is a General Purpose Code which was placed in service on January 1, 1947.

203 Area Code Prefixes

Our reverse phone lookup will analyze the three-digit prefix of any 203 area code phone number and will show which telecommunications company and rate center it was initially assigned to. This prefix code data may help to determine the U.S. carrier, Connecticut geographic region, and local calling area associated with the phone number.

Prefixes by Company

Company Number of Prefixes
SOUTHERN NEW ENGLAND TELCO DBA FRONTIER COMM OF CT 331
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CT 60
NEW CINGULAR WIRELESS PCS, LLC - DC 51
SPRINT SPECTRUM, L.P. 44
CABLEVISION LIGHTPATH, INC. - CT 36
TELEPORT COMMUNICATIONS AMERICA, LLC - CT 33
LEVEL 3 COMMUNICATIONS, LLC - CT 25
MCIMETRO ACCESS TRANSMISSION SERVICES LLC - CT 24
OMNIPOINT COMMUNICATIONS, INC. - CT 22
GLOBAL CROSSING LOCAL SERVICES, INC. - CT 20
PAETEC COMMUNICATIONS, LLC - CT 18
CHOICE ONE COMMUNICATIONS, INC. - CT 15
VERIZON NEW YORK, INC. 15
AT&T - LOCAL 14
COMCAST IP PHONE, LLC 7
METROPCS, INC. 5
BANDWIDTH.COM CLEC, LLC - CT 4
CONVERSENT COMMUNICATIONS OF CONNECTICUT, LLC - CT 4
MCIMETRO ACCESS TRANSMISSION SERVICES LLC 4
CTC COMMUNICATIONS CORP. - CT 3
TC SYSTEMS, INC. - NY 2
ONVOY, LLC - CT 1
PAETEC COMMUNICATIONS, INC. - NY 1
PEERLESS NETWORK OF CONNECTICUT, LLC - CT 1

Prefixes by Rate Center

Rate Center Number of Prefixes
NEW HAVEN 135
STAMFORD 93
BRIDGEPORT 91
NORWALK 54
DANBURY 53
WATERBURY 52
GREENWICH 26
MERIDEN 24
ANSONIDRBY 17
WESTPORT 16
MILFORD 14
WALLINGFD 14
DARIEN 13
FAIRFIELD 13
HUNTINGTON 13
TRUMBULL 13
BRANFORD 10
CHESHIRE 9
NEW CANAAN 8
WILTON 8
WOODBURY 8
BYRAM 7
GUILFORD 7
MADISON 6
NAUGATUCK 6
NEWTOWN 5
OLDGRNWICH 5
RIDGEFIELD 5
SEYMOUR 4
WOLCOTT 4
GEORGETOWN 3
REDDING 3
XXXXXXXXXX 1

Other Connecticut Area Codes

Lookup phone numbers starting with other Connecticut area codes: